X-Git-Url: http://git.droids-corp.org/?p=beacon-rx-433.git;a=blobdiff_plain;f=main.c;h=82f12d7cc28f1233a2ba3b0036670259c5f66a86;hp=d60f4a8b59139b3ec3a2fa464d8ae7907185cb4f;hb=HEAD;hpb=d8833c63c5a5daf57288f1bc080c6eb47e5e1e9c

diff --git a/main.c b/main.c
index d60f4a8..82f12d7 100644
--- a/main.c
+++ b/main.c
@@ -19,9 +19,24 @@
 #endif
 
 /* port B */
-#define BUZ_BIT   0
-#define RADIO_BIT 2
-#define LED_BIT   4
+#define BUZZER_BIT    0
+#define BUZZER_ON()   PORTB |= _BV(BUZZER_BIT)
+#define BUZZER_OFF()  PORTB &= (~_BV(BUZZER_BIT))
+
+#define RADIO_BIT  2
+#define RADIO_READ() (!!(PINB & (_BV(RADIO_BIT))))
+
+#define BUTTON_BIT 3
+#define BUTTON_IS_PRESSED()  (!(PINB & (_BV(BUTTON_BIT))))
+
+#define LED_BIT    4
+#define LED_ON()   PORTB |= _BV(LED_BIT)
+#define LED_OFF()  PORTB &= (~_BV(LED_BIT))
+
+#define MODE_NO_FILTER     0
+#define MODE_FILTER_THRES1 1
+#define MODE_FILTER_THRES2 2
+#define MODE_MAX           3
 
 static uint32_t bitfield;
 
@@ -330,30 +345,24 @@ static uint8_t get_input(int i)
 #ifdef HOST_VERSION
 	return !!x[i];
 #else
-	return !!(PINB & (1 << RADIO_BIT));
+	return RADIO_READ();
 #endif
 }
 
-static void set_output(int16_t i)
+#ifndef HOST_VERSION
+static void beep(void)
 {
-	int8_t detected = 0;
-
-	if (cpt_filter > 250)
-		detected = 1;
+	uint16_t i;
 
-#ifdef HOST_VERSION
-	printf("%d fil_fond=%d fil_harm1=%d fil_other=%d\n",
-	       i, fil_fond, fil_harm1, fil_other);
-	printf("%d pow_fond=%d pow_harm1=%d pow_other=%d cpt_filter=%d detected=%d\n",
-	       i, pow_fond, pow_harm1, pow_other, cpt_filter, detected);
-#else
-	/* when we receive, output a square signal at 625 hz */
-	if ((detected == 1) && (i & 4))
-		PORTB |= (1 << BUZ_BIT);
-	else
-		PORTB &= ~(1 << BUZ_BIT);
-#endif
+	for (i = 0; i < 1000; i++) {
+		if (i < 250 && (i & 1))
+			BUZZER_ON();
+		else
+			BUZZER_OFF();
+		wait_period();
+	}
 }
+#endif
 
 /*
   The CPU runs at 8Mhz.
@@ -364,11 +373,17 @@ static void set_output(int16_t i)
  */
 int main(void)
 {
+	int8_t detected = 0;
+	uint8_t mode = MODE_FILTER_THRES2;
 	int16_t i;
+#ifndef HOST_VERSION
+	uint8_t button = 0, button_filter = 0;
+#endif
 
 	/* led and buzzer are outputs */
 #if defined(__AVR_ATtiny45__)
-	DDRB |= (1 << LED_BIT) | (1 << BUZ_BIT);
+	DDRB |= (1 << LED_BIT) | (1 << BUZZER_BIT);
+	PORTB |= (1 << BUTTON_BIT); /* pull up */
 #endif
 
 	i = 0;
@@ -376,12 +391,42 @@ int main(void)
 
 	while (1) {
 
+		/* wait until 200us is elapsed since previous call (5Khz) */
 		wait_period();
+		detected = 0;
+
+#ifndef HOST_VERSION
+		/* filter button */
+		button = 0;
+		if (BUTTON_IS_PRESSED() && button_filter < 10) {
+			button_filter++;
+			if (button_filter == 10)
+				button = 1;
+		}
+		else if (!BUTTON_IS_PRESSED())
+			button_filter = 0;
+
+		/* change mode if button is pressed */
+		if (button) {
+			uint8_t j;
+
+			mode ++;
+			if (mode >= MODE_MAX)
+				mode = 0;
+
+			for (j = 0; j <= mode; j++)
+				beep();
+
+			/* reset input history */
+			bitfield = 0;
+		}
+#endif
 
 		/* push one bit in bitfield */
 		bitfield <<= 1UL;
 		bitfield |= (uint32_t)get_input(i);
 
+		/* filter the input */
 		apply_filters();
 		mean_pow(&pow_fond, fil_fond);
 		mean_pow(&pow_harm1, fil_harm1);
@@ -396,10 +441,57 @@ int main(void)
 		else if (cpt_filter > 0)
 			cpt_filter--;
 
-		set_output(i);
+		switch (mode) {
+			case MODE_NO_FILTER:
+			case MODE_FILTER_THRES1:
+				/* low threshold, some risk of false positive */
+				if (cpt_filter > 100)
+					detected = 1;
+				break;
+			case MODE_FILTER_THRES2:
+				/* high threshold */
+				if (cpt_filter > 250)
+					detected = 1;
+				break;
+			default:
+				break;
+		}
+
+#ifdef HOST_VERSION
+		/* display values */
+		printf("%d fil_fond=%d fil_harm1=%d fil_other=%d\n",
+		       i, fil_fond, fil_harm1, fil_other);
+		printf("%d pow_fond=%d pow_harm1=%d pow_other=%d "
+		       "cpt_filter=%d detected=%d\n",
+		       i, pow_fond, pow_harm1, pow_other, cpt_filter, detected);
+#else
+		if (detected)
+			LED_ON();
+		else
+			LED_OFF();
+
+		/* if filtering is disabled, just copy the radio input
+		 * on the buzzer */
+		if (mode == MODE_NO_FILTER) {
+			if (RADIO_READ())
+				BUZZER_ON();
+			else
+				BUZZER_OFF();
+		}
+		/* with filtering enabled, output a square signal at
+		 * 625 hz if beacon is detected */
+		else {
+			if ((detected == 1) && (i & 4))
+				BUZZER_ON();
+			else
+				BUZZER_OFF();
+		}
+#endif
 
 		i ++;
+
 #ifdef HOST_VERSION
+		/* exit when all samples are processed */
 		if (i >= sizeof(x))
 			break;
 #endif